In 19th-century Japan a master samurai trains a young band of assassins from childhood. His final test for them is to fight each other to the death, ensuring that only the strongest-willed and ruthless amongst them would survive. After being forced to murder her childhood friend, the young assassin Azumi is deeply traumatized by the experienced but still determined to continue her mission to defeat powerful warlord that has recently risen to power. Her rage builds throughout her journey, leading up to an epic bloodbath in the final confrontation against her foes.